A comparative study of BSF layers for InGaN single-junction and multi-junction solar cells

The tunability of the InGaN band gap energy over a wide range provides a good spectral match to sunlight, making it a suitable material for photovoltaic solar cells. The ineffectiveness of single junction solar cell to convert solar full spectrum into electrical energy leads to transparency loss in addition with excess excitation loss. An efficient BSF layer is an essential structural element to attain high efficiency in solar cells. In this work the impact of the BSF layer for InGaN single-junction and multi-junction solar cells is studied using the computational numerical modeling with Silvaco ATLAS simulation technique. The open circuit voltage (Voc) and circuit current density (Jsc) characteristics of the simulated cells and the variation of external quantum efficiency as a function of solar cell structures have been studied. For the optimized cell structure, the maximum Jsc = ۱۴.۶ mA/cm۲, Voc = ۳.۰۸۷ V, and fill factor (FF) = ۸۸.۱۵% are obtained under AM۱.۵G illumination, exhibiting a maximum conversion efficiency of ۳۶.۱%.